Cure following surgery for bladder cancer is limited by recurrence of the original tumor or by the development of new primary tumors in this multifocal disease. If the cure rate is to be significantly improved, adjuvants to surgery will be necessary. Chemotherapy has not been incorporated into the armamentarium of the urologist or oncologist in the treatment of advanced bladder cancer, much less adjuvant therapy, largely because of limited clinical data identifying agents effective in this neoplasm. A suitable animal model might serve to aid in the search for effective single or combination chemotherapy for bladder cancer. Since FANFT (N-4(5-nitro-2-furyl)-2-thiazoly1) formamide) induced murine bladder tumors closely resemble their human counterpart grossly and histologically, we are monitoring the effect of several chemotherapeutic regimens on the incidence, size and stage of primary bladder tumors. Ninety percent of C3H/He mice ingesting 0.1 percent FANFT for 11 mos. will have bladder tumors. In our initial study seven treatment regimens were initiated after 10 mos. on FANFT. Three weeks of chemotherapy did not significantly reduce the incidence of subsequent tumors compared to a control group, however, each agent significantly reduced tumor size as reflected by bladder weight. Cyclophosphamide (Cy) in combination with 5-fluorouracil or adriamycin produced the greatest inhibition of tumor growth. BIBLIOGRAPHIC REFERENCES: Soloway, M.S.: Single and combination chemotherapy for primary murine bladder cancer. Cancer. 36:333-340, 1975. Soloway, M.S., and Martino, C: Prophylaxis of bladder tumor implantation - Intravesical and systemic chemotherapy. Urology. 7:29-34, 1976.